Demographic Transitions and
Equitable Water-Use in the Reconquista River Basin, Province of Buenos
Aires (Argentina)

by

Moira Zellner

INTRODUCTION

From the origins of human communities,
the first waterworks responded, in most cases, to evident and immediate
needs of the population and its economy. They were therefore small projects
for satisfaction of drink and hygiene, irrigation, energy, navigation,
flood attenuation, conceived and exploited in many cases independently
from one another. In that context, water demand was very low compared to
the supply. Water was a natural gift, a renewable resource of infinite
availability and, therefore, human populations assumed that it should be
free (Capurro et al, in preparation). The growth of demand (due to increase
in number of users and units of consumption) determined the increase of
size of such waterworks, the consequent appearance of interference and
interaction with the hydrological cycle -scarcity- and a competition between
sectors of users.

In addition, the quality of both
superficial and underground water resources started to deteriorate, as
a consequence of human activity, especially in big urban concentrations.
Many watercourses were not fit for any type of usage, generating infested
and degraded areas in the surroundings. The response to these processes
was a change in the conception of water as a natural gift, a limitless
renewable resource. Water has ceased being an entirely renewable resource
(its supply has decreased in time).

From the 1,400 million cubic kilometers
of water in the world, only 1% is in the hydrologic cycle, of which half
is in lakes, and rivers. Even so, there is more than enough water to cover
current and future demand. The problem is that it tends not to be
where it is needed, or it is of poor quality.

The amount of water used at the community
level depends on various factors. Among them, we find climate (more water
is needed in arid areas compared to humid areas), and socio-economic levels
of the population. But mainly, water demand depends on its availability.
People adapt to available volumes of water, so it could be stated that
the greater the volume supplied, the greater its consumption level. Another
important factor that affects water demand is existing service infrastructure,
i.e. piping systems, treatment, storage and distribution. The policies
implemented by the authorities can also be used to regulate water use.
Those related to consumption records and prices are probably those that
affect demand the most. Finally, the efficiency of technology to extract
and use water can affect its demand. Better technologies would allow a
greater availability of water, both for urban and agricultural use (Capurro
et al, in preparation).

One of the most important problems
in designing water strategies is related to water assignment policies and
establishing priorities for different uses. The most common policy of price
fixation is a canon mainly conceived to recover costs. This type of uniform
price is not fixed as a function of the volume used, and is widely criticized
because it lacks incentives to control water usage.

An important cost of water supply
relates to its conduction from the place of production to place of consumption.
Consequently, the nearer a water source is to a city, the more attractive
it will be as exploitable resource. Generally, urban users can pay much
more for each unit of water volume because transportation costs are divided
among individuals and companies.

The hydrological sector constitutes
a system depending on activities and processes, among them are agriculture
and fishing, energy, industry, transportation, population dynamics, ecosystem
preservation, recreation. As such, its integrated planning must take into
account the available previsions of the development of these activities
and processes. Uncertainties in determining these changes in development
will affect the quality and even the validity of planning strategies.

In Argentina, the policies for water
management were created as a response to regional growth and to problems
that appeared during its development. The nation first, and the provinces
later, followed this process and this is how currently there is a great
disparity of criteria along the country. In many provinces, there is no
water legislation that accounts for an integrated approach to this issue.
Nevertheless, different institutions were created that coordinate, administer
and regulate the development and management of water resources. With respect
to a price for water, no policy has been applied to encourage its efficient
use. The value of the canon is generally insignificant and fixed by political
criteria more than by economic efficiency. In many cases, it is counterproductive
in the sense that it provides free access to agriculturists inexperienced
in irrigation systems, leading to elevation of groundwater table and salinization
(Capurro et al, in preparation).

The use of water for agricultural
use in Argentina depends on the provinces, which have the political right
to manage their natural resources. The pampas region in Argentina, which
concentrates most of the country's population, industrial activity and
agricultural activity, is a great demanding area of water. An increase
in demand is expected, not only due to urban growth or industrial activity,
but also due to the important appearance of irrigation. For this reason,
it is necessary to define water management strategies considering all the
elements in the water equation.

Purpose

The purpose of this study is to propose
policies that allow for equitable water allocation between competing activities
in the Reconquista River Basin, located in the
Province of Buenos Aires (Argentina). This area expands to the northwest
of the greatest metropolitan area of Argentina, the Metropolitan Area of
Buenos Aires (MABA). The waterhead of this basin is located in a predominantly
agricultural and agro-industrial area. Towards the river's mouth, urban
and industrial density increases, as well as its pollution levels. Most
of the basin lacks sanitation infrastructure, and the main water supply
are the underground aquifers and water tables nearer the surface, in some
cases contaminated with fecal bacteria and industrial pollutants.

To accomplish this objective, it
is necessary to understand the underlying interaction of population in
environment, in terms of different types of transitions and their stabilization.
The information used was:

Demographics in the basin;

Data on industrial discharges;

Water use and sewage demand by partido.

Equitable allocation policies are those
which allow a certain volume of water per capita for basic human needs
and economic development. Often, these are competing demands, especially
due to the lack of sustainable management of the resources. This study
aims to define sustainable levels of use of water resources, and to propose
allocation between activities.